SHERMAN OAKS - A big rig and a cement truck collided on the San Diego (405) Freeway in Sherman Oaks this morning, causing a spill of automotive fluids and resulting in lane closures.

The crash on the southbound side of the freeway near Valley Vista Boulevard was reported at 3:54 a.m., said California Highway Patrol Officer Francisco Villalobos.

The wreck caused a 20-minute closure of all southbound lanes beginning at 4:08 a.m., Villalobos said. The car-pool and two left lanes were then reopened while Caltrans crews worked to clean up the three right lanes, he said.

All remaining lanes were reopened about 6 a.m., the CHP reported.

It was not immediately clear if anyone was hurt.